Some air conditioning apparatus of the prior art use heat media (cold liquid and hot liquid) from a heat source apparatus (heat source facility) for heat exchange precools or preheats a heat medium circulated between a heat source unit and an indoor unit (air conditioning unit). An exemplary disclosed air conditioning apparatus activates a heat source apparatus at a time of day calculated on the basis of various types of data including the temperature of a liquid, measured at night, the liquid being included in a pipe connecting a heat source unit and air conditioning unit, after which the air conditioning apparatus fully opens a valve of an indoor unit scheduled to be operated on that day in a forcible manner, and precools or preheats the indoor unit before the indoor unit is actually used (see Patent Literature 1, for example).